Plants, whether in the ground or in pots, planters or similar containers, need periodic watering to survive. A number of schemes have been developed over the years to assure a plant receives a continuous supply of water, while maximizing the period between watering. Many of these schemes have involved providing a pot or planter with a built-in reservoir for storing water and a mechanism for supplying the plant with a constant flow of water from the reservoir.
For example, U.S. Pat. No. 262,379 issued to E. K. Dean on Aug. 8, 1882, describes an automatic watering device comprising a container designed to collect rain water that is stored in a reservoir and planters for containing plants. The planters are positioned in the container and include tubes that project down into, and are fluidly coupled with, the reservoir of the container. Water moves up into the planter through a wick in the tube. U.S. Pat. No. 283,966 issued to E. B. Chappell on Aug. 28, 1883, discloses another variation on the concept of the planter containing a reservoir in which a tube filled with soil projects down into the reservoir of water and acts as a wick to move water up to the soil surrounding the plant. Unfortunately, the devices disclosed in these patents require use of an external reservoir surrounding the container in which the plant is planted, which in certain contexts is visually unacceptable, cannot be accommodated in the space available or is otherwise unacceptable.
Of more recent vintage is U. S. Pat. No. 4,756,121 issued to A. Wild on Jul. 12, 1988 ("the '121 patent"), which discloses an irrigation device consisting of a container that encloses a sealable reservoir for holding and dispensing water. The container has a tightly sealable opening for introducing water into the reservoir. A portion of the container wall has a concave indentation that forms a chamber which projects into the water reservoir. The chamber is open at the top and is intended to contain soil and receive a plant growing in the soil. A lower portion of this chamber has capillary dimension openings which open into the water reservoir to allow water in the reservoir to come into contact with the soil in the chamber. These openings, in effect, act as a water-air exchange mechanism allowing water to enter the soil as air enters the sealed water reservoir. The device works on the principle that, given the reservoir is sealed, and the openings between the reservoir and soil in the chamber are extremely small, the exchange of water and air is slowed and thereby prevents the soil from being water-logged. The '121 patent mentions that the device can be buried in a flower bed or flower box; however, to seal the water reservoir the opening through which water is added would have to be accessible, and thus located at or above ground level. This limits the depth to which the device can be buried in the soil.
It is known to use a tube to deliver water to a reservoir at the bottom of a pot, with the tube extending up through soil in the pot or pot liner positioned above the reservoir. See, for example, U.S. Pat. No. 5,921,025 to G. Smith ("the '025 patent"). While the device of the '025 patent is believed to function satisfactorily for its intended purpose, it suffers from an important limitation. Because the sidewall of the pot or liner in which the reservoir is received extends a substantial distance above the top or cover of the reservoir, the device of the '025 patent occupies a relatively large space. This is disadvantageous when space constraints prevent use of a relatively large watering device.
Although, the patents discussed above all disclose apparatus that continuously supply water to a plant on a regular basis, none provide a separate watering reservoir which can be used with a wide variety of planters and can be buried in a flower or vegetable garden. Nor do they describe a watering reservoir which can be unobtrusively used with a planter such that it does not affect the aesthetics created by the plant and planter.